A speedster is someone or something remarkably fast. The word often describes people who move with exceptional speed, like a track star who leaves competitors behind or a soccer player who zooms past defenders. You might hear a coach say, “That new player is a real speedster!”

The term also applies to fast vehicles, especially sleek cars or motorcycles built for speed rather than comfort or cargo space. Classic sports cars from the 1950s and 1960s were often called speedsters. In comic books and superhero stories, speedster refers to heroes whose superpower is moving at incredible velocities, like The Flash, who can run faster than the speed of sound.

While speedster usually carries a sense of admiration for quickness and agility, it can occasionally suggest someone moves so fast they're reckless or careless. But most of the time, calling someone a speedster means you're impressed by their speed, and watching them in action is exciting.